The CB-316 black Buna-N non-marring vacuum cup (-5 to 250F) is .19 in diameter. It is for use on all our vacuum tools with the exception of the Roto-Pic and the PV-500. The cups are ESD Safe (10 - 10 ohmssq.)Specs amp; FeaturesCup, Heat Resistant (250F), Application: Designed for high temp, non marring applications - ESD Safe, Quality: , Surface Resistivity : 10-10 ohmssq, Shape: Round, Trade Name: Penvac , Material: Black Buna-n, OAL: .20 (5.08mm), Tip Width: .188 (4.76mm) dia.